Sir Philip Sidney wrote An Apology for Poetry (also known as A Defence of Poesy) around 1580–1581, though it was published posthumously in 1595. The work is considered one of the most important early works of literary criticism in English.
Why the answer is 3 – Stephen Gosson’s The School of Abuse:
Stephen Gosson, a contemporary of Sidney, published The School of Abuse in 1579.
In this pamphlet, Gosson launched a scathing attack on poets, poetry, and the stage, accusing them of promoting immorality, idleness, and corruption of society’s values.
Ironically, Gosson dedicated The School of Abuse to Sidney himself, perhaps expecting his support or approval.
This public dedication and polemic attack stirred Sidney to respond — not necessarily as a personal retaliation but as a broader defense of poetry and its moral and intellectual worth.
Sidney saw it necessary to defend poetry from the Puritanical moralism and utilitarian views being espoused by Gosson and others. He thus framed poetry as not only compatible with morality but as a noble art form that teaches and delights — echoing classical principles (like those from Horace: "docere et delectare").